It tells the story of Nick Guest, a homosexual man taken in as a lodger by the family of his university friend Toby, whose father was recently elected as an MP in the Tory landslide that accompanied Margaret Thatcher's rise to power. That's pretty much what this book is about: being gay in Britain in the 1980's. Nick is forced to pursue his affairs in secret, though the entire family is basically aware he's gay. In the final section of the book, Nick's sexuality becomes tangled up in connection with an insider trading scandal that threatens the job of the MP Gerald .
That last section is actually quite heartbreaking, as Nick deals with unpleasantly becoming the center of attention and becoming a persona non grata in the household (his surname Guest is a thinly disguised metaphor), while having to endure with the long demise of his former lover due to AIDs. However, that's only about 100 pages out of a 450 page book, the bulk of which are really quite dull. Nick is a rather shallow character who has a lot to say about Henry James and Rachmaninov and what have you, but he lacks such depth that he's a very difficult character to like. The first 350 pages of this book is little more than fancy parties, social hobnobbing, summering in France, and the occasional line of cocaine--you can read pages and pages without ever being convinced that anything has actually happened.
Maybe that's the point: until AIDs and scandal put his lifestyle under the harsh social spotlight, Nick's obsessions are quite trivial. I can understand the metaphorical purpose of being lulled into a false sense of security in the dizzying word of the socialite to only have the rug pulled out under Nick, but that really doesn't excuse this book from being excruciatingly dull.